Bloomberg News and Ad Age, citing unnamed sources, reported this week that food company Kraft Heinz Co. is rumored to be taking over the confectionery company that once belonged to its Kraft side of the business.

Shares of Mondelez International spiked as much as 12% last Wednesday after a report surfaced.

According to Bloomberg, Kraft Foods Inc. changed its name to Mondelez International Inc. in 2012 after the spin-off of its North American grocery business, which was then known as Kraft Foods Group Inc.

In 2013, Berkshire and 3G took ketchup maker H.J. Heinz private. In 2015, Berkshire and 3G merged Heinz with Kraft Foods Group. The combined company has gained in market value as 3G slashed costs by cutting jobs and shutting factories.

In June, Mondelez attempted to acquire chocolate maker Hershey, but that offer was unanimously rejected by the Hershey board. At the time, observers speculated that Mondelez was seeking the merger in order to not become a target for acquisition itself.

Bloomberg News cited Swiss economic magazine Bilanz for the information. There have been no comments from the parties involved.